__________________Paul Adams reports from Washington. The explosions occurred within seconds of each other close to the finish line on Boylston's street in the center of Boston. Four hours into the race there were still plenty runners on the street, and the crowds were dense. Television picture showed smoke billowing up from among the flags lining the route. One runner collapsed apparently struck by an object seconds later as terrified onlookers tried to get away. Picture showed another plume of smoke rising from the second blast down the road. Emergency workers immediately began tearing at the pavement barriers and flag poles to get the wounded behind. There were clearly many injured people. Injured spectators were carried to the nearby medical tents set up to look after exhausted runners.________________保罗?亚当斯从华盛顿发回报道.爆炸发生在波士顿中心的波尔斯东街道马拉松比赛终点线附近,两起爆炸相隔几秒钟.比赛已经进行了四个小时的时间,街道上仍然有许多选手,人群非常密集.电视画面显示,道路两旁的彩旗中突然浓烟翻腾.几秒钟后,当惊慌失措的观众试图逃离现场时,一名运动员很明显受到物体撞击而倒地.画面显示,这条道路不远处第二个爆炸地点又燃起浓烟.急救工作人员立即撕开人行道栅栏和旗杆,救治伤者.很明显爆炸造成多人受伤.受伤的旁观者被带到附近用于照料疲惫的运动员的医疗帐篷.